                1. Field of the Invention        
The present invention relates to graphene oxide, and particularly to the green synthesis of reduced graphene oxide (rGO) using Nigella sativa seed extract and its applications.                2. Description of the Related Art        
One of the recent advances in pharmacological research has been the use of novel drug delivery systems, and also the increasing application of monoclonal antibodies and oligonucleotides for therapeutic purpose. Functionalized nano-sized graphene has been used as a drug carrier for in vitro intracellular delivery of anticancer chemotherapy drugs. It has been found that nano-graphene with a biocompatible polyethylene glycol (PEG) coating displays high passive in vivo tumor uptake and could be used for effective photo-thermal ablation of tumors in a mouse model. On the other hand, many groups have developed graphene-based biosensors to detect various biomolecules via different mechanisms. Graphene-based nanomedicine, although still in its infancy, appears to be encouraging and may bring novel opportunities for future disease diagnosis and treatment.
Graphene is an atom-thick monolayer of carbon atoms arranged in a two dimensional honeycomb structure, and it is a basic building block for other graphitic materials, such as graphite and carbon nanotubes. Because of their unique and desirable electrical, optical, mechanical and chemical characteristics, graphene, graphene oxide (GO), and reduced graphene oxide (rGO) have been extensively studied for a variety of applications, such as nanoelectronics, sensors, energy storage, nanocomposites, etc., including biomedicine. The potential of graphene as a nanocarrier for drug delivery, gene delivery and nanomedicine has been demonstrated for possible cancer therapies. In addition, the improved synthesis and versatile surface modification of graphene has opened up new avenues for research on the nanoscale. In this regard, using “green” methods in the synthesis of nanoparticles has received attention, as conventional chemical methods are expensive and require the use of hazardous chemical and organic solvents.
Thus, the green synthesis of reduced graphene oxide (rGO) nanoparticles using Nigella sativa seed extract solving the aforementioned problems is desired.